I was satisfied with the book. It's not great Grisham, which usually entails detailed courtroom drama or attorney hijinks, but it was a pleasant interlude of an afternoon and evening. It is an airport book, one you pick up on the way to somewhere else. In this somewhere else, I wish I had been physically in Camino Island, but no.
Grisham seems to be trying to renew an old maxim of mystery writers, that every author should try to shine a spotlight on a world that the reader has no knowledge of: poisons, locked room murders, how to use poisons, conmen and their cons, and in this case, Rare book thievery. As ever with Grisham, it's touch and go if the criminal gets away with it.